1. Field of the Invention
The present invention relates to filter assemblies, and more particular to a filter assembly with manifold for multiple filter element housings and filter element housing coupling therefore.
2. Background Information
Filtration systems, traditionally considered a fluid treatment, can also be considered as a part of contamination management, which can be defines as relating to the analysis and optimization of processes with regard to the cleanliness of components, systems and the purity of the fluids used. In today's hydraulic systems, the hydraulics and mobile hydraulics industry, smaller, lighter and more powerful components are currently being used compared to only a decade ago. The use of these components also means that the demand of system cleanliness is now much higher, as has been shown by various studies. As much as 90% of all hydraulic system outages are due to increased contamination. This failure rate applies to more than classic hydraulics industry.
Contamination management, such as through the design and implementation of appropriate filter assemblies, is also a key issue in the automotive industry, in which the use of electrohydraulic systems is on the rise. In this context, hydraulic or fluid power systems are used in a general sense for all industries. In the past, fluid power systems were equipped with system filtration units, which cleaned the system during commissioning and then had the task of maintaining system fluid cleanliness at a constant level, e.g. by using commissioning filter assemblies and initial brief maintenance intervals followed by changing over to system filtration. This approach frequently no longer suffices due to the growing demands made of today's hydraulic systems (extended maintenance intervals and mounting cost pressure).
Pre-commissioning flushing is performed in large systems in the hydraulics industry to quickly bring the contamination down to an acceptable level.
In fluid treatment applications, filtration units include i) disposable units in which the filtration media and housing are integrated into a single use unit, often called “spin-ons” due to common threaded attachment technique; ii) replaceable units in which the filtration media is formed in an element or cartridge that can be removed from a unit housing forming a filter assembly; and iii) filtration units with cleanable media, such as by back-flushing.
Thus a filter element, also called a filter cartridge, within the meaning of this application, is a unit including filter media that is configured to be received in a filter assembly housing. The filter assembly is one or more filter housings and associated filter elements together with other elements of the unit such as a control, test points, particle counters, bypass valves, etc.
It is known to form a filter assembly with several filter elements coupled together in series such as for staged particulate filtration. A representative example of this has been sold by the applicant under the mark FILTRATION STATION® and which assembly is capable of flushing, filtering, and monitoring ISO cleanliness with user-defined, automatic features. The assembly is designed to transfer fluid through two filter elements in series for staged particulate or water/particulate removal. See also the MKF50™ brand Base-ported high pressure dual filter manifold mounted assembly from the applicant.
Where several filter element housings are incorporated into a filter assembly the filter element housings may be designed for manifold mounting and often feature both the inlet and outlet ports on a common surface. This type of mounting eliminates the need for connection hose and fittings and is beneficial when available space is minimal. Manifold mounting also reduces pressure drop and the potential for leakage. The manifold supports each filter element housing and includes the couplings to connect the associated filter elements in series or parallel or combination thereof as designed.
In a multi-filter element housing configuration using a manifold, the manifold is often one of the most expensive pieces of the system and time consuming to manufacture. The cost of replacing the manifold is quite expensive when elements become worn.
There is a need for a cost effective, efficient, filter assembly with manifold for multiple filter element housings and filter element housing coupling therefore.